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The present invention relates generally to printers and more particularly to an apparatus for making tactile impressions, such as a Braille matrix, on paper. The tactile impressions may be felt through the skin by visually impaired persons. A variety of systems for representing letters, words, or thoughts with tactile impressions on paper now exist. For example, a commonly used system, developed by Louis Braille in the early 1800's, uses predetermined combinations of raised circular dots, or "dimples," to represent letters of the alphabet.
In the Braille system, for example, each English language letter is represented by a combination of 1-6 raised dots. Dots for a particular letter are grouped together in two vertical columns, each column having up to three dots.
Communications using tactile impressions on paper are an important vehicle for allowing visually handicapped persons to communicate with others. Unfortunately, many of the printers available to make such tactile impressions are complex and expensive machines, which many visually handicapped persons cannot afford to own. Furthermore, the available machines are
o often simply too large, noisy and unreliable to be a workable tool for the visually impaired.
Moreover, many of such tactile printers can only use particular types of paper, further increasing the cost of providing Braille material to the blind. Also, many printers are large, heavy to transport, and difficult and expensive to maintain.
Many tactile printers use impact technology to create raised dots, and thus are very noisy and mechanically unreliable. Such printers are often too noisy to function effectively in an office environment that a blind person may wish to work in.
In addition, many of the tactile printers commonly available give poor quality impressions on paper. Others cannot use standard paper that is commonly available and used by sighted persons. Still other printers may only use particular sizes of paper, which, in some applications, may be inappropriate or difficult to use. This is particularly true if, for example, a visually impaired person wishes to do a large spread sheet or to print or "read" graphics. Still further, some printers take too long to operate, such that when connected to a word processor, a blind typist may spend a considerable period of time before being able to "read" what he or she has typed by touching the tactile impressions. Other printers are difficult for the visually impaired to load with paper.
Overall, tactile printers should be more widely available to visually handicapped persons. The large size, complexity, high-cost and poor performance of many commonly available tactile printers reduce the amount of "written" material that is available for the visually handicapped. This, in turn, may preclude the blind from obtaining jobs that they otherwise are capable and willing to perform. The lack of "readable" material and reduced opportunities for jobs further isolates the blind from the rest of society and prevents them from assimilating into the environment and work places of sighted persons.